The serological study of antibodies to avian leukosis/sarcoma viruses (ALSV) and reticuloendotheliosis viruses (REV), and the in vitro study of the infectivity of REV for human cells have been completed, and the results indicate for the first time that humans/human cells cab be infected with these viruses. Experiments for detecting integrated ALSV & REV in human genome are in progress. The results of the case-control study of lung cancer in the meat industry indicate that butchers, meatcutters and persons who worked in the stockyard and killing/dressing areas of abattoirs were at extremely high risk of lung cancer, even after controlling for smoking. Contact with raw meat was also a risk factor. These findings point to viruses such as bovine leukemia virus as possibly responsible. Packing and wrapping of meat was also associated with increased risk Chemical analysis of urine for muconic acid in supermarket workers in Albuquerque is complete, and statistical analysis is in progress. Mortality analyses of the Baltimore and Missouri cohorts of workers (N=36,000) in a meatcutter and poultry unions has commenced, as is also analysis of a case-control study of tumors of the hemopoietic/lymphatic systems in the meat industry. Follow-up of over 30,000 poultry workers and controls in a Chicago Pension Fund is in progress, as is also an ecologic study of cancer mortality by cattle, poultry and pig inventory in North Carolina. Analysis of serum levels of TCDD in Australian sprayers is complete, while analyses of other dioxins and furans are in progress.